A steering mechanism known from the German No. OS No. 31 22 370; U.S. Pat. No. 4,438,827 to Armin Lang shows each reaction chamber having associated restrictor orifice in the outlet chamber feeding via variable speed responsible restrictor to a tank. In such a steering mechanism, the hydraulic reaction acting on the steering control valve piston is used to create a simulated steering reaction and also for stabilizing the steering control valve piston as well as for obtaining a delicately sensitive steering adjustment.
A disadvantage of such steering mechaism is the fact that in critical cases in normal driving the usual system pressure may not be high enough for sufficient hydraulic reaction or for the mechanical centering of the steering control valve piston in order to be sure of adequate stabilization of that valve. In fact, the reaction chambers can act as damping chambers with no increase of the static actuating forces of the springs which act on the valve by having certain dimensions of the restrictor orifices. However, such damping opposes rapid shifting of the valve and thus leads to undesired delays in steering control, as a result of which the driver may be unable to correct swerving from the roadway quickly enough due to rapid steering inability.